1. Field of the Invention
This invention relates to a method for converting standing wave vibrations into a linear or rotary motion and to a standing wave motor which is driven by this method. More particularly, this invention relates to a method and a standing wave motor which are capable of moving a moving member with high efficiency by use of at least one vibrator generating a standing wave in a vibration member.
2. Description of the Prior Art
It has been known that ultrasonic vibrations caused in an elastic body by applying a periodic voltage thereto can be converted to a rotary or linear motion. A variety of vibration wave motors driven on this principle have been hitherto proposed. The motor of this type has an advantage that it enjoys simplicity and compactness of structure compared with an electromagnetic motor because it has no need for any electromagnetic means such as a coil and that it can produce a rotary motion of relatively high torque even at a low speed. Therefore, the vibration wave motors are attracting keen attention.
The conventional vibration wave motors are classified into the following four types.